Starting a review
Open a finished game in the Library and choose Review. Review is not available from the recording screen or for an unfinished game: that is deliberate, for fair play.
How long it takes
Usually a minute or two for a whole game on a recent phone. Deeper settings take longer. You can stop at any time and keep what has been found.
Key moments
Plyfolio marks the moves where the evaluation changed most. Each shows what was played, Stockfish's line, and the evaluation in words and numbers, from White's side.
Exploring a position
From any key moment, choose Explore this line to step through the engine's moves on the board, or try your own.
Battery
Stockfish works the processor hard while it runs, so a long review uses some battery. In Settings, Analysis, you can choose a shorter time per move.